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1.
Interleukin-4 as a potent inhibitor of bone resorption   总被引:5,自引:0,他引:5  
A possible role of interleukin-4 (IL-4) in the regulation of bone turnover was assessed by employing a 45Ca prelabeled-fetal mouse long bone culture system. IL-4 inhibited the bone resorption stimulated by parathyroid hormone (PTH), PTH related protein (PTHrP), 1 alpha, 25, dihydroxy-vitamin D3 [1 alpha, 25 (OH)2 D3], interleukin-1 alpha and - 1 beta (IL-1 alpha, IL-1 beta) and prostaglandin E2 (PGE2). Anti-IL-4 on monoclonal antibody abolished the inhibitory effect of IL-4 on the bone resorption. These results suggest that IL-4 may play an important role on the inhibitory regulation of bone resorption.  相似文献   
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In this study, we investigated the effects of different stocking densities water quality and blood parameters during the transportation of the Siberian sturgeon (Acipenser baerii). Experiments were carried out in high-density polyethylene tank with three different stocking densities (50, 100 and 150 kg/m3) for 20 h. Ammonium nitrogen (NH4-N) and nitrite nitrogen (NO2-N) were measured in the water samples. The erythrocyte, leucocyte, haematocrit (HCT), haemoglobin (Hb), cortisol, and sodium ion (Na+) were measured in blood samples. Ammonium nitrogen and nitrite nitrogen concentrations in the water have increased in parallel with the stocking density depending on the time. In the highest stocking density, the maximum levels of NH4-N and NO2-N at the 16th h reached 2.64 mg/L and 4.74 mg/L, respectively. Erythrocyte, leucocyte, HCT, and Hb values did not differ significantly between the experimental groups (p > .05). The results showed that fish could be transported safely for 20 h in 15℃ water temperature at 50 kg/m3 stocking density; however, stocking density of 100 kg/m3 and over could threaten fish welfare and health as from 16th h.  相似文献   
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Four chiral C2‐symmetric diols were synthesized in a straightforward three‐step reaction and demonstrated excellent enantioselectivities and good overall yields. Their catalytic activities were examined via the addition of diethylzinc to various aldehydes. The enantioselective addition of diethylzinc to 2‐methoxybenzaldehyde gave the corresponding chiral secondary alcohol with high yields (up to 95%) and moderate to good enantiomeric excess (up to 88%). All synthesized ligands were evaluated in the addition of diethylzinc to various aldehydes in the presence of an additional metal such as Ti(IV) complexes. Chirality 28:593–598, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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In this speculative essay, I examine two evolutionary developments underlying the enormous success of the human brain: its capacity to acquire knowledge and its variability across individuals. A feature of an efficient knowledge-acquiring system is, I believe, its capacity to abstract and to formulate ideals. Both attributes carry with them a clash between experience of the particular and what the brain has developed from experience of the many. Both therefore can lead to much disappointment in our daily lives. This disappointment is heightened by the fact that both abstraction and ideals are subject to variability in time within an individual and between individuals. Variability, which is a cherished source for evolutionary selection, can also be an isolating and individualizing feature in society. Thus the very features of the human brain which underlie our enormous evolutionary success can also be a major source of our misery.  相似文献   
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Surgical reconstruction of the penis is challenging because of the many cosmetic and functional (e.g., sexual intercourse and voiding) requirements that must be addressed. Since the free sensate osteocutaneous fibula flap was first described for total penile reconstruction in 1993 it has been widely accepted, with its advantages and minimal shortcomings. In this article, the authors present the longest follow-up of biologically male patients with free fibular phalloplasties. Since 1994, 18 biologically male patients with total penile losses for various reasons were treated with free sensate osteocutaneous fibula flaps. All patients were included in the study. The ages of the patients ranged between 20 and 26 years (mean, 22.2 years). The average follow-up period was 5.4 years (range, 1 to 9 years). Patient satisfaction was evaluated by a questionnaire regarding both quality of orgasm and daily activities. Conventional radiographic imaging, magnetic resonance imaging, and bone mineral densitometry were performed to evaluate the fate of the bony component of the flap. Also, sensibility was evaluated by bulbocavernous reflex and penile somatosensory evoked potentials testing in nine patients. Six patients married, and five of them had six children. Most patients and their partners reported pleasurable sexual intercourse and orgasm. Conventional radiographs of the fibular bone in neophalluses showed robust, calcified bone structure without any evidence of bone resorption or fracture. The magnetic resonance images showed the cortical substance and spongiosum of the bone marrow, which are characteristic signs of bone viability. After intravenous injection of gadolinium, the neophallus bone showed uptake of contrast medium. Viability of neophallus bone was shown even at 9-year follow-up (the longest follow-up in the literature). Dual energy x-ray absorptiometry measurements of the penile bone grafts showed that fibular components in the penis had bone mineral density values that were close to but lower than those of intact fibula in the same subjects. These results were considered as evidence of viability of bone grafts. Neural integrity was found between the nerves of the neophallus and the residual penile bodies by both bulbocavernous reflex and penile somatosensory evoked potentials tests. In conclusion, free sensate fibula flap phalloplasty provides the cosmetic and functional requirements that an ideal penis should have. All results put an end to the discussion that the fibular component of the neophallus could resorb. Constitution of neural integrity is important in terms of pleasurable sexual intercourse. The authors believe the free sensate osteocutaneous fibula flap should be considered as the standard in penile reconstruction.  相似文献   
7.
Combining law and the brain as a matter for study requires the integration not just of two apparently remote fields of study but also of two profoundly different orientations towards research and study. We believe that, in spite of the difficulties, such a combination, perhaps even emerging in a new specialized discipline in the future, will not only enrich both fields but is the ineluctable consequence of the current assault on the secrets of the brain. The effort to bring the fields together is therefore a worthy task, and this issue is the first systematic effort to test this expectation.  相似文献   
8.
Peroxidation of the membrane lipid structure of red blood cell leads to haemolysis and anaemia in haemodialysis patients. Dietary constituents of antioxidant vitamins and trace elements may play an important role in protecting against oxidant damage. In this study, the effects of supplementation of vitamin C and zinc on osmotic fragility and lipid peroxidation of erythrocytes were investigated in 34 zinc-deficient haemodialysis patients. Sixteen sex- and age-matched normal volunteers acted as controls. Patients were randomized to receive vitamin C (250 mg day(-1)), zinc (20 mg day(-1)) or a placebo treatment for 3 months. The levels of vitamin C, zinc, malondialdehyde (MDA) and osmotic fragility were measured initially and 3 months after supplementation. Mean serum concentration of vitamin C and zinc increased significantly in the groups at the end of the respective study periods. Supplementation with vitamin C and zinc improved osmotic fragility, and decreased the level of MDA in the groups, but some side-effects (i.e. nausea, vomiting, fever, muscle pain, weakness) were observed during the zinc treatment. The results showed that the supplementation of both treatments decreased osmotic fragilty and MDA in zinc-deficient haemodialysis patients. However, vitamin C treatment was found to be safer than zinc supplementation.  相似文献   
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Sol–gel and gel–sol phase transitions of κ-carrageenan in pure water and in KCl solution were studied using photon transmission technique. Photon transmission intensity, Itr, was monitored against temperature to determine the sol–gel and gel–sol temperatures (Tsg and Tgs) and activation energies (ΔHsg and ΔHgs). It was observed that Tgs was notably higher than Tsg due to the hysteresis on the phase transition loops. Tgs and ΔHgs values were also higher for gels containing KCl than for those without KCl. The increase in carrageenan content caused an increase in both critical temperatures and activation energies for the gels prepared in pure water and in KCl solution. Increases in the KCl/carrageenan ratio, raised both Tgs and Tsg. Similarly ΔHsg was elevated by the increase in cation content of the gel. These results were interpreted as the formation of stronger gels in the presence of KCl in water.  相似文献   
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